Functionalization of sexithiophene with electron-donating methylsulphanyl groups

Novel soluble sexithiophenes (6Ts) ?-functionalized with electron-donating methylsulphanyl groups are reported. The resulting processable sexithiophenes, two examples of which are shown in the Figure, have optical gaps that can be finely tuned around the value for unsubstituted ?-6T. The observed liquid-crystal behavior described here indicates a high degree of molecular organization in the solid in at least one case.